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Old 05-07-2015, 06:54 AM   #1
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How to block almost all outgoing traffic (except VPN) from a specific IP in my router

hi all.

I would like to know, how i block all outgoing internet traffic in my router, (exept VPN traffic) from my NAS. My Synology NAS is connected to a VPN service with OPENVPN. As far as i know, the VPN traffic is on port 1194.

So i have attached the configuration in my router below this message. The policy i have added in the picture, applies to only (my NAS)

I want to achieve this, because sometimes the vpn tunnel fails, (and unloads the IP-Table package) and my real IP is exposed..So if i block it from my router, i am safe.

But i have run into an issue. I am also using a program called Flexget, which runs a script, many times a day. And i can see in its log file, that it cant do URL lookups. So i am guessing that i am blocking dns requests aswell? So how do I, let's say, allow VPN traffic, and googles DNS ( (and perhaps something else for it to function properly??)

You are probably thinking that i should ask in the forum of my router, but i already did. And they don't know how to solve such a.. technical problem
And you guys inhere know ALOT about networking...

Thanks for your time! Hope to hear from you
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Old 05-07-2015, 11:55 AM   #2
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Have you tried THIS
Old 05-07-2015, 03:00 PM   #3
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Some notes, not solutions.

You have two things that collide here. One is that you want a vpn and then want to move outside of it for dns. In a true vpn you can't allow that by default or shouldn't. It does expose the tunnel.

Yes, tunnels are hard to maintain. The more secure get the more impossible it is to get it to work across the internet.

Not sure exposing your IP is protected by your openvpn deal.

I might be tempted to run either a virtual machine router or get a new router inbetween that acts as your openvpn and have some sort of fail over or reboot.

I assume your isp (by normal issues) is more the cause of the vpn getting dropped. Maybe not.

Last edited by jefro; 05-07-2015 at 03:15 PM.
Old 05-09-2015, 02:05 PM   #4
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Thanks for your reply guys... Gave me something to think about!


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